Effect of high-amplitude forcing on turbulent combustion intensity and vortex core precession in a strongly swirling lifted propane/air flame

S. V. Alekseenko, V. M. Dulin, Yu S. Kozorezov, D. M. Markovich

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

The present work reports stereoscopic particle image velocimetry (PIV) measurements in a strongly swirling nonreacting jet and partially premixed lifted flame. The spatial distributions of the average velocity and components of turbulent kinetic energy were calculated from the measured ensembles of the instantaneous velocity fields. A pronounced bubble-type vortex breakdown was observed for the studied flows. Based on proper orthogonal decomposition (POD) of the PIV data and on estimates of velocity fluctuation spectra by a laser Doppler velocimetry (LDV) probe, it was concluded that the combustion did not fundamentally affect the type of coherent structures in the strongly swirling flow: a pair of secondary helical vortices was induced by a precessing vortex core in both cases. Because a strongly swirling jet flow is usually insensitive to weak forcing, strong perturbations were superimposed on the flow bulk velocity to force the formation of ring-like vortices in the flow and to investigate the possible outcomes on the turbulent combustion process. The forcing frequency was below that of the precession. Based on the CH* chemiluminescence signal, it was observed that the forcing provided an increase in the turbulent combustion rate near the flame onset, as the entrainment of ambient air to the rich mixture must have increased. Moreover, for a forcing amplitude typically above the magnitude of reverse flow inside the bubble-type recirculation zone, a dramatic suppression of the vortex core precession took place in the reacting case. This effect was accompanied by a quasi-periodical vanishing of the recirculation zone due to interaction of the forced ring-like vortices with the lifted flame.

Original languageEnglish
Pages (from-to)1862-1890
Number of pages29
JournalCombustion Science and Technology
Volume184
Issue number10-11
DOIs
Publication statusPublished - 1 Oct 2012
Externally publishedYes

Fingerprint

turbulent combustion
Propane
swirling
precession
propane
flames
Vortex flow
vortices
air
Air
vortex rings
Velocity measurement
particle image velocimetry
bubbles
vortex breakdown
jet flow
premixed flames
chemiluminescence
entrainment
Swirling flow

Keywords

  • Large-scale vortices
  • Lifted flame
  • Particle image velocimetry
  • Precessing vortex core
  • Swirling jet
  • Swirling partially premixed flame

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)
  • Fuel Technology
  • Energy Engineering and Power Technology
  • Physics and Astronomy(all)

Cite this

Effect of high-amplitude forcing on turbulent combustion intensity and vortex core precession in a strongly swirling lifted propane/air flame. / Alekseenko, S. V.; Dulin, V. M.; Kozorezov, Yu S.; Markovich, D. M.

In: Combustion Science and Technology, Vol. 184, No. 10-11, 01.10.2012, p. 1862-1890.

Research output: Contribution to journalArticle

@article{315f7fec463a4924b0cc980e1fc48337,
title = "Effect of high-amplitude forcing on turbulent combustion intensity and vortex core precession in a strongly swirling lifted propane/air flame",
abstract = "The present work reports stereoscopic particle image velocimetry (PIV) measurements in a strongly swirling nonreacting jet and partially premixed lifted flame. The spatial distributions of the average velocity and components of turbulent kinetic energy were calculated from the measured ensembles of the instantaneous velocity fields. A pronounced bubble-type vortex breakdown was observed for the studied flows. Based on proper orthogonal decomposition (POD) of the PIV data and on estimates of velocity fluctuation spectra by a laser Doppler velocimetry (LDV) probe, it was concluded that the combustion did not fundamentally affect the type of coherent structures in the strongly swirling flow: a pair of secondary helical vortices was induced by a precessing vortex core in both cases. Because a strongly swirling jet flow is usually insensitive to weak forcing, strong perturbations were superimposed on the flow bulk velocity to force the formation of ring-like vortices in the flow and to investigate the possible outcomes on the turbulent combustion process. The forcing frequency was below that of the precession. Based on the CH* chemiluminescence signal, it was observed that the forcing provided an increase in the turbulent combustion rate near the flame onset, as the entrainment of ambient air to the rich mixture must have increased. Moreover, for a forcing amplitude typically above the magnitude of reverse flow inside the bubble-type recirculation zone, a dramatic suppression of the vortex core precession took place in the reacting case. This effect was accompanied by a quasi-periodical vanishing of the recirculation zone due to interaction of the forced ring-like vortices with the lifted flame.",
keywords = "Large-scale vortices, Lifted flame, Particle image velocimetry, Precessing vortex core, Swirling jet, Swirling partially premixed flame",
author = "Alekseenko, {S. V.} and Dulin, {V. M.} and Kozorezov, {Yu S.} and Markovich, {D. M.}",
year = "2012",
month = "10",
day = "1",
doi = "10.1080/00102202.2012.695239",
language = "English",
volume = "184",
pages = "1862--1890",
journal = "Combustion Science and Technology",
issn = "0010-2202",
publisher = "Taylor and Francis Ltd.",
number = "10-11",

}

TY - JOUR

T1 - Effect of high-amplitude forcing on turbulent combustion intensity and vortex core precession in a strongly swirling lifted propane/air flame

AU - Alekseenko, S. V.

AU - Dulin, V. M.

AU - Kozorezov, Yu S.

AU - Markovich, D. M.

PY - 2012/10/1

Y1 - 2012/10/1

N2 - The present work reports stereoscopic particle image velocimetry (PIV) measurements in a strongly swirling nonreacting jet and partially premixed lifted flame. The spatial distributions of the average velocity and components of turbulent kinetic energy were calculated from the measured ensembles of the instantaneous velocity fields. A pronounced bubble-type vortex breakdown was observed for the studied flows. Based on proper orthogonal decomposition (POD) of the PIV data and on estimates of velocity fluctuation spectra by a laser Doppler velocimetry (LDV) probe, it was concluded that the combustion did not fundamentally affect the type of coherent structures in the strongly swirling flow: a pair of secondary helical vortices was induced by a precessing vortex core in both cases. Because a strongly swirling jet flow is usually insensitive to weak forcing, strong perturbations were superimposed on the flow bulk velocity to force the formation of ring-like vortices in the flow and to investigate the possible outcomes on the turbulent combustion process. The forcing frequency was below that of the precession. Based on the CH* chemiluminescence signal, it was observed that the forcing provided an increase in the turbulent combustion rate near the flame onset, as the entrainment of ambient air to the rich mixture must have increased. Moreover, for a forcing amplitude typically above the magnitude of reverse flow inside the bubble-type recirculation zone, a dramatic suppression of the vortex core precession took place in the reacting case. This effect was accompanied by a quasi-periodical vanishing of the recirculation zone due to interaction of the forced ring-like vortices with the lifted flame.

AB - The present work reports stereoscopic particle image velocimetry (PIV) measurements in a strongly swirling nonreacting jet and partially premixed lifted flame. The spatial distributions of the average velocity and components of turbulent kinetic energy were calculated from the measured ensembles of the instantaneous velocity fields. A pronounced bubble-type vortex breakdown was observed for the studied flows. Based on proper orthogonal decomposition (POD) of the PIV data and on estimates of velocity fluctuation spectra by a laser Doppler velocimetry (LDV) probe, it was concluded that the combustion did not fundamentally affect the type of coherent structures in the strongly swirling flow: a pair of secondary helical vortices was induced by a precessing vortex core in both cases. Because a strongly swirling jet flow is usually insensitive to weak forcing, strong perturbations were superimposed on the flow bulk velocity to force the formation of ring-like vortices in the flow and to investigate the possible outcomes on the turbulent combustion process. The forcing frequency was below that of the precession. Based on the CH* chemiluminescence signal, it was observed that the forcing provided an increase in the turbulent combustion rate near the flame onset, as the entrainment of ambient air to the rich mixture must have increased. Moreover, for a forcing amplitude typically above the magnitude of reverse flow inside the bubble-type recirculation zone, a dramatic suppression of the vortex core precession took place in the reacting case. This effect was accompanied by a quasi-periodical vanishing of the recirculation zone due to interaction of the forced ring-like vortices with the lifted flame.

KW - Large-scale vortices

KW - Lifted flame

KW - Particle image velocimetry

KW - Precessing vortex core

KW - Swirling jet

KW - Swirling partially premixed flame

UR - http://www.scopus.com/inward/record.url?scp=84868674222&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84868674222&partnerID=8YFLogxK

U2 - 10.1080/00102202.2012.695239

DO - 10.1080/00102202.2012.695239

M3 - Article

VL - 184

SP - 1862

EP - 1890

JO - Combustion Science and Technology

JF - Combustion Science and Technology

SN - 0010-2202

IS - 10-11

ER -